Lid lifting mechanism for dishwashers and the like



April 13, 1954 C. HOLLERITH LID LIFTING MECHANISM FOR DISHWASHERS ANDTHE LIKE Filed May 15, 1953 5 Sheets-Sheet l v INVENTOR- CHARLESHaLLE/ww ATTORNEY April 13, 1954 c. HOLLERITH 2,675,010

LID LIFTING MECHANISM FOR DISHWASHERS AND THE LIKE Filed May 15, 1955 3Sheets-Sheet 2 IN V EN TOR. (HA RL 5 IIOLLE/E TH A TTa/e/vE r April 13,1954 c. HOLLERITH LID LIFTING MECHANISM FOR DISHWASHERS AND THE LI KE 5Sheets-Sheet 3 IN VEN TOR. Hou 5/21 TH Filed May 15, 1953 CHARL E5 A TTOE/V5 Y Patented Apr. 13, 1954 UNITED STATES PATENT OFFICE LID LIFTINGMECHANISM FOR DISH- "WASHERS AND THE LIKE Charles Hollerith,

Jackson, Mich, assignor to Lake State :Products, Inc., conporationof-Michigan Jackson, Mich a AllplicationiMar 15, 1953, Serial .No.355,2'72i6 Claims. (Cl. 134-:58)

motors and will "operate 'on2 or 3 watts. Since motors for this purposeare ordinarily merely requiredto rotatecams which actuate switchescontrolling circuits for solenoids, motors and the like, it is apparentthat very little power is required. I am familiar with lid liftingmechanism for dishwashers and the like 'wherein a solenoid circuit isenergized by a timer to actuatethe'lid lifting mechanism, and "in thisinstance, considerable power is available to trip a latch or the likeagainst the force of a spring loaded lid. The present invention isconcerned with lid lifting mechanism'which is'sprin'g loaded whenthedishwasher lid is manually closed and which requires relatively littleforce to release the latch means and this force is within the capacityofa small conventional timer motor.

It 'is a primary object :of the invention'to provide lid liftingmechanism "for raising the lids oi dishwashers and the like and whereinspring means :are loaded :upon :closing the lid and rela- L tivelylittle force is required .to release latch means permitting the lid .tobe lifted under the influence of the springmeans.

Another object or" the invention is to provide lid lifting mechanism fordishwashers and the like and wherein the lifting mechanism is renderedinoperable when the lid is manually lifted.

Another object :of the invention fiS to provide lid lifting mechanismfor dishwashers and the likewhich is relatively simple and economical ofmanufacture and assembly.

Other objects or the invention and the invention andthe-inventionxitself will becomeincreasingly apparent from aconsideration of the following description and drawings, wherein:

Figure 1 is a fragmentary perspective view showing the inside front wallof "a dishwasher cabinet and lid lifting mechanism embodying theinvention;

Fig. 2 is a fragmentary sectional view showing the lid in full lines'inthe closed position andin dotted lines in the raised position;

Figure 3 is an enlarged view looking on the front of the outer frontwall of the cabinet, where a removable cover plateis'located, thecoverplate 2 being removed to expose the upper end o fit-he l-ifilifting rod, a push wire for turning a cam onthe timer shaft for closingthe heater and timermotor circuit and a safety switch which renders allthe dishwasher circuits inoperative when the lid is opened;

Figure 4 is a transverse sectional view of the frcnt wallof the cabinet;

Figure 5 is an enlarged View of the latch means illustrated in Figure 1;

Figure 6 is an enlarged fragmentary view 0f the spring coupling betweenthe timer and thelid actuator cam shaft; and

Figure 7 is a view looking on theright-hand end of'Fisure 6.

Referring now to the drawings and particular- 1y Figure 1, I haveindicated at 10 the front wall of a cabinet for a dishwasher or thelike, viewed from the interior of the cabinet, preferably having anL-shaped reinforcing member Ili at the topthereof. The cabinet isofconventional form being generally square in cross section and comprisingwalls extending to a height "such .:as 36 inches. The cabinet serves toreceive a vat 9 in'which the articles to be washed are placed, this vathaving a hinged lid 12 and a depending peripheral :fiang 13 adapted :tohave seated engagement with aflange twithin'the vatwhen the lid isclosed. To maintain the lid .in fully open position, I provide anysuitable means such :asan arm pivoted to the lid and having an L-tshapedslot therein through which a .pin on a side wall of the vat projects. Ina conventional manner, when the arm is "moved so that the pin engagesthe "bottom end portion of the slot the lid will be held in openposition and the lid may be closed by bringing the :pin inte alignmentwith the long pcrtion of the slot. lid is provided with a handle ill-atthe front thereof having "a plate 136 adapted to engage .a lift rod 11.Handle [4 is preferably mounted that may have limited movement relativeto the lid to insure that plate 16 engages the upper endof rod ii. Thehandle it is mounted upon the lid flange l3 throughthe medium :ofresilient grommets IE or rubbenfor example, which permit the handle tobe flexed downwardly relatively to the lid 12. In its depressedcondition, withthe lid closed, there will be som clearance between theupper endof the rod H and the-lidhandle l4. Normally, afterthe lid hasbeen raised, "hythe release of the rod I l, as described later, the rodwill be manually depressed before the lid-is closed again. It isdesired, however, that the lid 'fiange J 3 should close againstthe vatflange 8 and the flexible mounting thereof extends above .pin 41b andlocated,

of the handle I4 permits the handle to be de-' fiected downwardly toengage the rod I1, after the lid flange has seated against the fllange 8and thereby insure that the rod I1 is properly set in its trip position;whereupon the flexible handle mounting will restore the handle to itsnormal position, as shown in full lines in Figure 2, when the handle isreleased.

Rod I1 which is square in cross section is mounted for vertical slidinmovement in an upper square guide slot 20 provided in the horizontalupper flange 2| of a plate 22 secured to the outer upper portion offront wall ID. The cabinet front wall I0 is formed with a generallyT-shaped opening 23 beneath member I I for a purpose to be described.Rod I1 also projects through a hole formed in a generally U-shaped strap24 pivoted laterally of rod I1 as indicated at 26. The upper face ofstrap 24 forms a seat for the lower end of a compression spring 21, theupper end of the spring abutting a washer 28 telescoped over rod l1 andlimited in upward movement by a pin 29. It will be noted that the rod iscurved to provide an offset straight portion 3| and spring 21 hassufiicient force when loaded by closing lid I2 to lift the straightportion 3| upwardly until the curved portion of the rod, indicated at32, is in spaced relation to the top edge 33 of a rectangular slotformed in plate 22.

It will be noted by reference to Figure 4 that the portion of lift rodI1 below curved portion 32 is disposed inside the front wall It of thecabinet and that the curved portion projects through wall opening 23 sothe rod straight portion 3| is disposed externally of wall II]. When thelid is closed and spring 21 is loaded, as illustrated in Figure 1, itwill be apparent that strap 24 tends to bias or force the lower end ofrod I1 to the left. Under these conditions, a generally U- shaped slot34 formed in rod I1 engages a latch 36 which is of generally L-shape andhas a horizontally extending U-shaped slot cut in the top flangethereof.

A plate 38 is secured to front wall It of the cabinet andis formed withan car 39 extending at right angles thereto having a square guide holefor a bar4 I. Bar 4| is preferably square in cross section and plate-38has a second ear 42 slotted to form a second guide means for bar 4 I. Tolimit movement to the left (Figure 1) of bar 4| it is provided with acollar 43 adapted to abut ear 42. When the lid is closed, one end of bar4! abuts or is closely adjacent to rod E1 and the opposite or left-handend of the bar abuts or is closely adja 'cent to a cam 44. Cam 44 has alift portion 45 whereby when the lift portion engages bar 4! the barwill be forced to the right and resultantly force the lower end of rodI1 to the right whereby the rod slot 34 will be moved out of engagementwith latch 36 and the loaded spring 21 will lift rod I1 upwardly untilpart of the straight portion 3| upper guide slot 23. It will be notedthat it is only necessary for the cam to overcome the relatively lightbiasing force of strap 24 to force rod |1 out of engagement with latch36. Cam 44 is mounted on the outer end of a shaft 46 which is coupled toa short shaft 41 extending from a timer generally indicated at 48 by aspring coupling 49. The spring coupling comprises an end bushing 41asecured on the shaft 41 by a cross pin 41b and having an axial slot 410open to the outer end of the bushing, into which the end portion 460:extends and carries a pin 46b, mounted perpendicularly with respect tothe with clearance, in the slot 4 410. A coil spring 48a is anchored atone end to the pin 46b and at the other end to the pin 41?). Normally,the shaft end 460 will lie at one side of the slot 41c, as seen inFigure '7. At the commencement of rotation of the shaft 41 the spring49a Will be tensioned and the pin 46b will be constrained to travel tothe opposite side of the slot as the shaft 46 is rotated. This stores upenergy which serves to move the cam 44 rapidly to present its low partto the left-hand end of the bar 4| after the cam has presented its highpart to this end of the bar for pushing the rod I1 to the releaseposition. The bar is thus free to be returned to its initial position inwhich the rod can be re-set for the next lid lifting operation.

The timer is of the conventional type used on dish-washers and the likewherein a relatively small electric motor 5| rotates a cam shaft andthrough cams controls operation of inlet and drain valves, electricalcircuits for motors actuating the impeller, pump and the like. Aspreviously pointed out, a motor of this type has relatively little powerbut I have found that relatively little efiort is required to overcomethe biasing action of strap 24- and release rod I1 from latch 36 andthat such effort is within the capacity of the timer motor. To aid insliding movement of bar 4| I preferably provide a curved spring 52 whichabuts plate 38 and has its end portions bent and formed to provide guideslots for the bar.

It will be noted that a. second cam 54 is mounted on shaft 46 and thatthis cam is formed to provide a notch 56 adapted to engage a shorthorizontally extending bent portion 51 of a push wire 58. The lower endof Wire 53 is bent to engage the lower end of a spring 59. which tendsto move the wire upwardly. The upper end of wire 58 is bent to engagethe lower surface of a pin 6| movable vertically in a guide slot 62formed in plate 22. Pin 6| is an integral part of a push button slidablein a cover plate 50 mounted on the outer side of cabinet front wall IIl.When the push button is forced downwardly manually the cam 54 andresultantly the timer cam shaft will be rotated.

To avoid undue noise when rod I1 is forced upwardly into contact withthe top of strap 24 and to limit upward movement of rod I1 I preferablyprovide a rubber cushioning washer 1| backed by a metal washer 12 andlimited in downward movement by a pin 13.

The lid is provided'with a prong 8| whereby whenever the lid is closed aswitch controlling element indicated at 82 will be forced downwardlyagainst the tension of a spring 83 and when the lid is opened theelement 82 will be lifted by the spring. Downward movement of element 82completes a circuit to the timer motor through a switch 84 and upwardmovement thereof opens the circuit whereby the timer will be stopped anytime the lid is lifted preventing the lift rod, I1 frombeing movedupwardly unless the lid is closed.

The operation of the mechanism will now be described. Upon manuallyclosing lid I2 rod I1 is forced downwardly loading spring 21 and thebiasing action of strap 24 forces the lower end of the rod slightly tothe left (Figure 1) forcing slot 34 of the rod over latch 36 to lock therod in a down or non-lifting position. Closing of lid I2 also closesswitch 84 which conditions the timer circuit for operatin the timermotor 5|. At the completion of the previous cycle of operations thetimer was stopped in the off position and after switch 84 is closed thepush button mounted on cover plate 60 is forced manually downwardly andby means of push wire 58 and cam 54 the timer is moved to the onposition and the timer starts operating. After a predetermined periodthe lift portion 45 of cam 44 forces bar 4! to the right (Figure 1)moving rod I! out of engagement with latch 36 and the rod is forcedupwardly under the influence of spring 21 to lift lid 12. It will benoted that manual opening of lid l2 breaks the timer circuit and stopsthe timer through opening of switch 84 sothat rod I! cannot be raised tolid lifting position unless the lid is closed.

I wish it to be understood that I do not desire to be limited to theexact details of construction shown and described for obviousmodifications will occur to a person skilled in the art.

I claim:

1. The combination with a dishwashing machine of the type having acabinet, a hinged lid on the cabinet, and an electrically operable timerincluding a shaft operable by a low powered motor, of mechanism forautomatically lifting the lid at the completion of a cycle of washingand rinsing operations, said mechanism comprising a rod mounted forvertical sliding movement alon a wall of the cabinet and adapted toengage and lift the lid by upward movement of the rod, spring meansadapted to be loaded by downward movement of the rod when the lid ismanually closed, latch means adapted to hold the rod in a downwardposition when the lid is closed, and mechanical means operable by thetimer shaft adapted to render the latch means ineffective whereby therod will be forced upwardly by the spring means to lift the lid.

2. The combination as described in claim 1 and wherein the circuit forthe timing motor includes a switch operable by opening and closing 6movement of the lid, and lid opening movement breaking said circuit andstopping the timer whereby the lifting rod cannot be forced upwardly bythe spring means when the lid is manually raised.

3. The combination as described in claim 1 and wherein the lower portionof the lift rod is adapted to be moved laterally, the latch meanscomprises inter-engaging portions on the rod and a fixed member, andmeans are provided effective upon loading of the spring means to biasthe lower portion of the rod laterally into latched position.

4. The combination as described in claim 1 and wherein the meansrendering the latch means ineffective comprises a cam on the timershaft, and movable means extending between the cam and the lower portionof the lift rod effective to move the rod laterally out of latchingengagement.

5. The combination described in claim 1 and wherein the lift rod has themajor portion thereof disposed inside the cabinet and adjacent the frontwall thereof, the upper portion of the rod projects externally of thecabinet to engage the lid, means are provided to bias the lower portionof the rod laterally into latched position, and the biasing means limitsupward movement of the rod,

6. The combination as claimed in claim 1, and wherein the said shaftincludes a spring coupling connecting the shaft with said mechanicalmeans, said means including a cam on said shaft and a bar movable bysaid cam to render said 1 latch means inoperative; said spring couplingbeing effective to move said cam for freeing the said bar to be restoredto its initial position when said rod operates to lift the lid.

No references cited.

